Private Internet Access (PIA) has a (hidden?) feature in port forwarding where it tries to keep you in the same port, even if you are connecting to a different server.

So if I connect to Canada and it gives me the port 50123, connection drops for any reason (modem, router, ISP, Proton...) and it reconnects to another country, let's say USA, or even a different server in the same country, if the port 50123 is available it's gonna give me that port, if not then tough luck here's a new port.

This is very useful to avoid having to update the port in services that are using it.